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arXiv · 2212.12973

Role of polarizations and spin-spin correlations of $W's$ in $e^-e^+ \to W^-W^+$ at $\sqrt{s} = 250$ GeV to probe anomalous $W^-W^+Z/\gamma$ couplings

Amir Subba·Ritesh K. Singh
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Abstract

We study anomalous $W^-W^+Z/\gamma$ couplings due to dimension-$6$ operators in the production process $e^-e^+ \to W^-W^+$ followed by semi-leptonic decay using polarizations and spin-spin correlations of $W$ bosons. The construction of some of the polarization and spin-spin correlation asymmetries required one to distinguish between two decay quarks coming from $W^+$ decay. We developed an artificial neural network (ANN) and a boosted decision tree (BDT) to distinguish down-type jets from up-type jets and used them to put constraint on anomalous couplings at International Linear Collider (ILC) running at $\sqrt{s} = 250$ GeV with integrated luminosities of $\mathcal{L} \in \{100 \ \text{fb}^{-1}, \ 250 \ \text{fb}^{-1}, \ 1000 \ \text{fb}^{-1}, \ 3000 \ \text{fb}^{-1}\}$. We find that the use of polarization and spin correlation observables, on top of the cross-sections, significantly improves the limits on anomalous coupling compared to the earlier studies.

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Amir Subba, Ritesh K. Singh. 2022-12-25. Role of polarizations and spin-spin correlations of $W's$ in $e^-e^+ \to W^-W^+$ at $\sqrt{s} = 250$ GeV to probe anomalous $W^-W^+Z/\gamma$ couplings. https://doi.org/10.1103/physrevd.107.073004

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